In general, it is known that fibers can be used to increase the strength of cementitious materials and gypsum products. See U.S. Pat. Nos. 4,105,739 and 4,133,928. Moreover, it is known that if the adhesion between the cementitious material and the reinforcing fibers is increased, that it can have a positive impact on the strength of the material. For example, in U.S. Pat. No. 4,257,993, glass fibers are coated with a resin or sprinkled with quartz sand to increase the adhesion. In U.S. Pat. No. 4,314,003, carbon fibers are coated with an epoxy resin having a fatty acid amine hardener. In U.S. Pat. No. 4,910,076, the fibers are coated with a reactive copolymer latex and a synthetic resin. In U.S. Pat. No. 4,916,012, carbon fibers are coated with epoxy resins and rubber latex. In U.S. Pat. No. 5,032,181, carbon fibers are coated with organometallic-based coatings and latex coatings are disclosed as promoting bonding between the carbon fibers and the cement matrix.
While the foregoing has improved the strength of cementitious materials, further improvement is still sought.